Allopatric speciation involves a physical separation of groups as they form new species; sympatric speciation does not

Ernst Mayr’s biological species concept

does not apply to organisms that reproduce asexually

Which statement about the morphological species concept is true?

Linneaus used one

Which species concept most emphasizes the evolutionary history of species?

The lineage species concept

In the Dobzhansky-Muller model, an ancestral population (aabb) splits into two lineages. Different mutations produce different new alleles in each population (Aabb in one population, aaBb in the other). All of the following genotypes would be viable except

AaBb

The Dobzhansky-Muller model

emphasizes gene interaction

All of the following statements about speciation are true except

evolution always occurs in speciation

Which of the following is least likely to lead to allopatric isolation?

A small lake dividing a population of butterflies

Geographic isolation

may decrease the probability, over time, that members of two separated populations can mate

A butterfly is separating into two different groups- one that lays eggs in the understory of bushes and the other that lays eggs in the tops of bushes. This butterfly species is most likely experiencing

sympatric speciation

Which statement about polyploidy in plants is true?

Allopolyploids are hybrid plants that result from the mating of two closely related species

The distinction between prezygotic and postzygotic isolation is whether

The isolation occurs before or after fertilization

Two geographically separated populations of butterflies begin to diverge in the time of day they are active. One group is active earlier in the day, and the other is active later. If this separation were to continue, it would most likely contribute to _____ isolation.

temporal

Prezygotic isolating mechanisms can arise from all of the following except

low fertility of hybrids

Refer to the figure below, which shows the frequencies of mating calls in two frogs in areas where they are in sympatry and areas where they are in allopatry. The mating calls are ______ diverged in regions of sympatry. Based on this result, one might predict that there has been selection to _______ prezygotic isolation in regions of sympatry, a phenomenon known as _______.

more; increase; reinforcement

Suppose that the natural ranges of horses and donkeys were to overlap. Which of the following statements best describes what would likely happen to the populations over time?

Because their hybrid offspring are not reproductively fit, reinforcement could strengthen prezygotic barriers

Two populations that were once isolated come into contact. Which of the following statements about what might happen after contact is false?

If hybrids are unfit, reinforcement of prezygotic barriers would be disfavored

Which is least likely to evolve via direct natural selection?

Hybrid infertility

Persistent hybrid zones, like those found in Bombina frogs in Europe, stay narrow due to